The blunt reality is that us meatbags are utterly ill-suited in every way to exist anywhere other than Earth (or someplace very Earth-like), and it requires a staggering amount of resources to climb uphill against that fact. I'm happy that we went to the moon (a truly mind-blowing achievement), and I hope that a human someday walks on Mars; but in an age of robotics, manned space travel is no longer the optimal way to explore or conduct research. Even its utility as a PR stunt has rapidly diminishing returns.
The good news is that the ever-growing sophistication of mechanical devices gives our species incredible "virtual fingers" to probe and interact with the cosmos, whether for research, or industry (such as asteroid mining, and perhaps someday, long-term terraforming).
And of course, I hold out hope that our cyborg/android/AI great-grandchildren will someday roam the stars in a way that we primates can only dream of.
There is no foundation for this argument to stand on.
Besides the fact that sending humans vs sending robots isn't a zero sum game, we're also sending robots out with decreasing frequency as well. "We should be happy to just send robots" would be great if we were actually sending robots. Here's hoping China and India pick up the mantle when Oppy and Curiosity finally shut down, I guess.
The reality is also that we don't learn much science with practical benefits for the hundreds of millions to billions of dollars we spend on these probes. Of course, we also get wildly poor returns on investment for the hundreds of billions to trillions of dollars we spend (in the US) on defense and health care. What we've decided is that it's worth it to spend a small amount of our money on the exploration of our universe, that discovery can be its own reward (and if there's a small chance in practical payoffs down the line, even better). We don't need to see what the surface of Pluto looks like, but I'm pretty excited to find out about it. Dismiss that as PR, but apply it equally.
This argument functions similarly to the one demanding we solve all the problems on earth before we start spending money on space. It assumes a way of allocating funds that doesn't match reality and demands unrealistic requirements not imposed on the favored approach.
> the fact that sending humans vs sending robots isn't a zero sum game
only if we pretend there's infinite money available. if sending a single human being to mars/moon is so expensive that NASA isn't capable of doing anything else.. then it is a zero-sum game.
> The reality is also that we don't learn much science with practical benefits for the hundreds of millions to billions of dollars we spend on these probes.
It's unfair to compare one probe against sending a human. The moon landing cost $150 billion. Is a human more valuable than 100 or 500 of these probes?
> Besides the fact that sending humans vs sending robots isn't a zero sum game
This is a good point. I'm certainly not advocating against humans going to space; I just think sending robots is a vastly better long-term ROI. And whether it's a hundred years away or ten thousand, someday a form of intelligent life will exist on this planet that is much better equipped (if not actively designed) to seek its destiny in the stars.
When a person says that we should be sending humans into space, they are implicitly claiming to know the ROI, (at least that it is greater than some amount).
I personally don't believe we should be doing human space exploration, because exploration with machines strictly dominates exploration with humans. The only reason for human space travel is if we value moving humans for its own sake (e.g. to reduce the risk of humanity getting wiped out in a comet strike). But I think that could be better handled with anti-comet measures and underground bunkers.
> When a person says that we should be sending humans into space, they are implicitly claiming to know the ROI
When a person says we shouldn't send people to space, is that also an implicit claim they know the ROI to be insufficient? And insufficient against what measure?
> exploration with machines strictly dominates exploration
Postulation, iteration and testing, re-iteration, re-testing. These are principals of both the scientific method and sound engineering design. I do not disagree significant progress can be made by exploration with mechanical devices, or organic test-beds, but grandly architectured schemes tend to fail over a costly amount of both time and financial impact, critical failure, than multiple iterated and tested solutions.
>When a person says we shouldn't send people to space, is that also an implicit claim they know the ROI to be insufficient?
Obviously. My point is that having an opinion either way implies knowing the ROI is greater/less than some cutoff.
>And insufficient against what measure?
According to economic theory, the measure is the ROI of the next best project. But even if you don't subscribe to this theory, I imagine most people implicitly judge projects by some criterion that can be expressed as a cutoff of ROI. E.g. most people don't believe we should be building an interstellar spaceship right now, because the ROI on such a venture would be too low.
>Postulation, iteration and testing, re-iteration, re-testing...
A bit confused here. From what I can see, exploration with robots is the path of iteration, while sending humans is the grand scheme. Do you see things differently? For example, there have been four successful Mars rovers starting in 1997. Each one has been incrementally bigger and better. Furthermore, improvements in computer and robotics hardware will happen regardless of investment by space exploration (I'm assuming improvements in the Mars rovers largely piggypacked on existing robotics technology, experts feel free to correct me), while improvements in human space travel will require specific investment in these technologies.
The ROI for a given bit of science over a one year span will almost always be a big negative. The ROI for "Science" over the last century is a huge portion of the GDP of the world.
I'd assert that for optimizing some mostly known process, building an ROI model for investment decisions is valid, but for long-term exploration of the unknown it's meaningless because you can't build a predictable model for ROI.
Where does "one year" come into it? ROI means the total discounted future returns divided by total present investment. Talking about ROI is nothing to do with short vs long term thinking.
ROI should always be taken to mean expected ROI. Now I'm not dogmatic when it comes to probability. If you say that the probability distribution of a given projects future returns is not well defined, that's fine. Nonetheless, we implicitly always use something roughly similar to probabilities when evaluating uncertain outcomes. I'm not even saying that doing this explicitly with numbers is even useful. I'm just saying that there is no fundamental difference between saying "we should(n't) do X" and calculating the ROI of X.
* require a constant supply of oxygen. Which is available effectively nowhere except deep inside gravity wells.
* require a constant supply of water. Which is available effectively nowhere. H may be everywhere, but O is nowhere convenient.
* require G-forces to be between 0.8 and 1.2 for long term survival. Can tolerate very brief exposure up to about 4G. This means the vast majority of planets are effectively uninhabitable just for that reason. And harshly limits the maneuvers possible to get there.
* require a sun-like source of radiative energy with a certain minimum intensity (one of the reasons people can't survive on Mars without additional UV exposure)
* require the presence, in small quantities, of half the elements with an atomic number up to 26, and several found further on. H, C, N, O, Na, Mg, Al, S, Cl, K, Ca, Fe, and I. Some of these are not very common, and they may be very hard to find. Not finding them first means it becomes impossible to have kids, increased occurrence of things like cancer, and a few years later it becomes lethal.
* require gravity. Which is massively inconvenient for operating ... well, anything really
* require radiation shielding against solar radiation for long term survival that requires about a hundred kilometers of atmosphere or several inches of metal (if you're to survive long term, for short excursions less isolation can be acceptable, also in Low Earth Orbit (like ISS) you're still partially shielded by the earth)
* require radiation shielding for charged particles that is provided by the earth's magnetic field, but requires metal barriers in outside of those fields
* require the sun's plasma barrier around the solar system to weaken interstellar background radiation to the point that the earth's atmosphere/reasonable thickness metal can actually stop it.
* require to be inside the galaxy, again to weaken certain types of radiation
* require a minimum distance to any supernova explosion of around 50 light years to survive (or yet more shielding)
* require to be in groups of at least 50 for long term survival (or we won't have enough gene variation and die off over time), even though short excursions can use a limited number of people. This is the low end of the estimates.
* require to be in groups of 2-3 people at least even for short term excursions or there will be severe psychological consequences
* require the presence of large masses of bacteria to fulfill certain bodily functions the human body can't actually do itself (best - but not only - example being digestion)
* require the presence of bacteria outside of the body to create compounds that we can't make ourselves. Some of these cannot be stored for any length of time, you need to take bacterial colonies or, better yet, plants + bacterial colonies with you and let them grow.
This isn't a complete list by any means. Human bodies will never go very far from Earth.
In the cosmic sense, Mars isn't terribly far, at least, or far off on most of these, given potential technological progress over the next few hundred years. I'm pretty confident humans will briefly visit Mars before 2040, and will probably maintain a continual presence, even as meat.
My understanding is that Mars has a dead core and no magnetic field, meaning severe problems with radiation, and even if we melted icecaps and thickened the atmosphere, Mars' lower gravity and lack of a magnetic barrier to solar wind would lead to gas particles escaping to space, and the atmosphere eventually thinning again.
I think that eventually would be measured in centuries or more. If we are able to solve the engineering challenge of terraforming Mars in the first place this kind of continual housekeeping won’t be an issue.
I wasn't thinking anything this ambitious. We can keep people alive in the crushing depths of the oceans for weeks/months/years at a time; the real limits there seem to be economic. We could do the same thing for tens or hundreds of people on Mars if we really wanted to. Living indoors/underground most of the time, dependent upon certain things being supplied from Earth (but otherwise some kind of closed cycle or local production for anything bulky), etc.
I lean towards the pessimistic side of humanity's future in space, but I don't see that being a practical problem. If we manage to figure out a way to create a viable atmosphere on Mars, it ought to be a relatively trivial add-on to supply enough atmospheric gasses to make up for losses to solar radiation.
That isn't even an add-on. In order to get from current atmosphere to breathable atmosphere, you already have to overcome the stripping effect of the solar wind, plus an additional amount. All you have to do is throttle the system back to just the replacement rate. It would require a continual energy investment, but as long as the lights can stay on, everyone can still breathe.
In the extreme long term, Mars may be a good place to try a planet-wide artificial magnetosphere, using high-temperature superconducting materials. That's a rather hefty bit of engineering for a planet that currently has no humans on it.
This is a rather static view of human bodies. Your list is nice, but it's about current limitations on the avarage 2014 human body living on Earth. Human bodies haven't always worked exactly like this and I'm convinced the evolution isn't about to get stagnant now. Quite the contrary, with the advancements in biotech we will surely be able to accelerate the adaptation process to non-Earth environments.
Queue discussion of what is "Human". If a life form can trace its origins to biotech experiments carried out by humans on other humans, is that resulting life form necessarily human?
Depends on the definition, as you predicted. In general I agree with Dawkins that mono definitions don't even make sense here. [1]
There never was an Australopithecus mother who gave birth to a Homo child, for every child ever born belonged to the same species as its mother.
However to give some rough idea, then in the context of this space exploration discussion, when I say "Human" I mean everything starting from the first person who learned how to cook [2], all the way to potential future versions where there's only a brain within a cyborg body.
While I agree with Dawkins as such on his point, I can also imagine a future in which both "mother" and "born" become a bit of an anachronism. In that future I wouldn't be overly comfortable simply slapping the label "human" on everything.
It is possible with space elevators and a series of Biosphere 2 style experiments. A series of five and ten year experiments can prove the feasibility of building hermetically sealed nuclear powered habitats. With space elevators they can be replicated outside the gravity well in space, spinning at 1G and properly shielded from radiation.
Nano tech developments make space elevators seem less and less crazy. It is not crazy to expect to happen in the next 40 years.
The thing to do is hermetically seal off some deep down mines with nuclear reactors and 30 people for 10 years and prove it can be done.
They have already tried to seal off humans to see if they could survive in a closed habitat for years. They failed.
Until we figure out a way to generate food without the use of plants and animals, we cannot explore space. The overhead of having to maintain plants and animals for food is just too great to make sustainable living elsewhere in the solar system feasible.
If everybody stopped trying to do something the first time they failed, no one would do anything or learn anything. Heck, science is all about systematically and methodically failing - that's what the null hypothesis is all about!
I almost wrote that we probably won't have permanent outposts in space within any of our lifetimes, but that isn't strictly true, is it, what with Skylab, Mir, and ISS? So let me posit that we will probably never see self-sustaining space habitats (whether in orbit around Earth or on some other body in the Solar System) within our lifetimes, nor within our children's lifetimes. That doesn't mean it isn't a worthy (or feasible) goal. Mankind has wondered about traveling to the moon for hundreds of years (if not thousands), and only recently has it become possible. Living somewhere other than Earth isn't really all that different, insofar that it is an engineering problem and not a scientific one, and unless some apocalyptic disaster strikes us, we have nothing but time in which to figure it out.
I definitely do not think we shouod stop trying. We need to look into non plant and animal based food, at least for calories and amino acids. Probably will need to research into catalysts which can take raw H2 and CO2 to convert into starches and such.
They failed mostly because they hadn't accounted for the way the concrete that the building was made from would continue to suck CO2 from the atmosphere as it cured, resulting in very low yields from the crops they intended to grow for food.
If you collected several varieties of extremophilic microorganisms from here on Earth, spent about 40 years resequencing their genes, and then shot those tailored organisms in cubesat-like dispersal capsules down into each gravity well, that overhead would take care if itself within a few millennia. First design the space-plankton, and then the space-whales can follow.
Waste recycling is difficult when you don't have an entire planetary biological system to work with. So why not start by trying to cover every rock in this system with a biofilm just one cell thick?
There was one fairly low budget attempt. Nobody ever said it was going to work the first time. I can imagine it taking 25 years to iron out all the kinks.
It's not like people figured out reliable trans-oceanic voyaging and navigation in a couple years. It was a long processes.
What would you suggest as a manned mission that isn't merely an expensive stunt?
As I understand it an Apollo style mission to Mars or Mercury is presently more like an early death sentence to cancer due to radiation exposure.
As best I understand the situation we really need to pull off a five year Biosphere 2 style mission here on earth in a hermetically sealed chamber deep underground. That is the current next step. But nobody has really tried.
Going to Mars, you have the following options right now.
You can shield the spacecraft from radiation with passive mass. That's relatively expensive option, but hardly technologically infeasible. The question is only the price of each kilogram on LEO, and that goes down steadily.
You can use spacecraft magnetic field. An interesting area with a bunch of research to do.
You can speed up the way to Mars, say, from 6-8 months today to 3 months, having to spend extra fuel at launch and at arrival. For that, you can e.g. revive Nerva-style engines.
A combination of these (and possibly other) methods brings Mars closer even for today's safety standards.
"If you recruited the Mars crew out of smokers and sent them to Mars without their tobacco you would be reducing their chance of getting cancer." - Dr. Robert Zubrin
I see this attitude a lot, and I suppose that there is a certain truth to it, but it always seems incredibly short sighted to me. I am never sure how to respond except:
-humans aren't meant to fly.
-humans are incredibly unsuited to cross large stretches of ocean.
-humans aren't built to travel faster than a horse's pace.
That's a bit of a straw man argument. Nobody's claiming that we can't; rather that to accomplish many of our goals, having a human as the physical actuator is a bad choice. Robots have the potential to perform nearly any given mission better than their human counterparts.
That was not the case during the development of ships, automobiles, or flight. The alternatives to those were "don't fly/explore/travel fast", not "have a machine do it for us". It's a different question. Increasingly even on Earth, satellites and drones explore our planet, not explorers with hiking boots. The same analogy applies to many kinds of space exploration.
On the other side of the coin: Sentiment is what drives resources to fund our exploratory efforts, and we like seeing humans do things. Additionally, the goal of colonization requires human presence nearly by definition.
The longer-term question is whether we'll change that definition, or continue to require the presence of biological humans to consider a planet effectively colonized. That may not always be the case: if a given planet can protect our collective civilization from extinction, does it matter whether that's secured by human actuators versus robotic ones?
I did not intend to set up a straw man. You are correct, however, that no one is arguing that we can't. Rather, they are arguing that we shouldn't. I don't agree with that position. Remember, early motor cars were nothing more than an expensive hobby, and one that was heavily criticized because of the noise and danger. Early aviation was also nothing more than an expensive hobby. Because there were people who wanted to push forward despite there being no obvious return on investment is why we have the developments we do in these and other fields. I and many others feel similarly about human space exploration. We feel that there is intrinsic value in it that is not readily captured in the ROI calculations. I grant that we are talking about a different order of magnitude in required resources, but I don't feel that qualitatively changes the argument.
I could also make some more technical arguments around the value of having a human on site to repair or refit instruments, to react to unexpected developments, and so on, but that is outside the scope of the argument I was trying to make.
You make a very good point about ROI for non-obvious investments.
I also agree with you that for many things like your general repair example, humans are better than robots for the time being. That's why I framed it as them having "the potential" to perform better. I think most would agree that our on-site manual superiority isn't going to last very much longer in the scheme of things; especially under scrutiny of cost/benefit.
What I'm trying to get at is the question of where we see humans' roles over the coming centuries with respect to space travel, and whether the sci-fi trope of humans on ships and colonizing planets on foot makes sense or is really something to aspire to, and at what point that falls apart as a utilitarian approach.
I agree it's not yet, but I agree with @lukifer that we'll outgrow ourselves as our technological grasp exceeds our biological one. And our reach has never known any bounds.
I see an important difference. Planes, boats and cars are technology. Before we had planes, there were scientific evidences that objects heavier than air could fly (= birds). This in fact was a strong motivation for people to develop the technology.
We can go on Mars, that's for sure, it's close enough. But intergalactic space travel is harder. Not because of the limits of our technology, but because of physics. Not only there is not evidence that it's possible but there are strong theoretical results that suggest that we can't simply "travel in hyperspace" as they do in Star Wars.
You seem to believe that science can solve these problems, but today science is what's stopping us from doing it.
Intergalactic travel may be implausible, but I've seen results that a civilization using Orion-drive-level technology - that is, using the kind of thing we could build today if we had the will to do so - could colonize the galaxy in a mere hundred million years. There's no scientific or technological barrier to that, only a political one.
Keeping an entire population of humans alive (possibly around 20,000 - 40,000 individuals [1]) on a space ship for at least 100 years (time required to reach Alpha Centauri with nuclear based propulsion [2]) is quite a technological challenge. So I wouldn't say it's just political, but I agree it's plausible.
Ok, but you get my point: there may be actual limits to the development of space travel technology. Your logic seemed to imply there was none. Sorry for speculating though.
To be clear, I'm not making the case that humans aren't "meant" to be in space. I'm referring to the practical obstacles to us both getting to space and surviving there for more than short periods, which is orders of magnitude more difficult thermodynamically relative to airplanes.
If someday we can create enclosed self-sustaining ecosystems in space, maybe I'll eat my words, but as it is, we have to send along huge fixed quantities of bio-support materials, using an exponential proportion of fuel (thanks to the tyranny of the Rocket Equation). It simply doesn't scale. And that's to say nothing of the prospect of decades-long interstellar journeys, or living off-planet permanently.
Sure, and I am not arguing against robotic exploration which is incredibly valuable, but I also consider human exploration to be incredibly valuable both from a strict scientific point of view and from the point of view that sometimes there is an intangible value in attempting and accomplishing incredibly difficult things.
The cost of fuel is a trivally-small cost in today's launches. Contrast your thinking with Elon Musk's: he wants to drive down the cost of launches by 99% to facilitate putting a colony on Mars.
You cannot know what Musk is actually believing. I'm sure that he is very passionate about enabling colonies on Mars and so on but he is also a businessman selling a product while having to deal with competition.
I tried to make this case back in August after the Spaceship One accident.
"Someone dying is devastating. Trying to conquer space a handful of people at a time is the slow and dangerous way of accomplishing this task. We should be building machines to explore the solar system. This can be done for a fraction of the cost, time, and it will allow him to allow us to iterate quickly.
In 100 years, more humans will live off earth if we iterate with machines, etc now than if we move slowly trying to reduce the risk in order to keep humans safe."
If you read the threads you get a lot of people who don't buy it.
Because we can iterate more quickly and conquer space faster. In 200 years, if we do it my way we'll have far more humans living in space than if we do it a few humans at a time.
The point that you're completely missing is that I'm not saying that humans shouldn't eventually head out into space, it's that we should quickly interate our machines and other technology before we make the big push.
> The point that you're completely missing is that I'm not saying that humans shouldn't eventually head out into space, it's that we should quickly interate our machines and other technology before we make the big push.
Which means we will never do it. People are not as concerned about the national debt because they don't think they will have to pay it. Ditto for a lot of other events and practices.
The related item to that short-sightedness is that things that don't excite the public won't get done. We are already dealing with a generation or two that didn't get their jet-pack, flying cars[1], cyberpunk, or space planes to vacation space stations. Getting the PR to get funding for something that won't happen in the current generation's lifetime is a no go.
1) yes, impractical and dumb, but it was a sign of the supercool sci-fi tech - hell, we don't even have an SST anymore
We didn't get our humanoid robots either. How about we finish that job then send a few thousand of them throughout the solar system? Start exploring, mining asteroids, building bases, building other robots in space, etc. We can justify the research money spent on them because it has a direct payoff:
Because your basically saying no human is going to get to journey into space in the near term, so why would the current generation fund it? No PR or dream, no funding. The possibility of Virgin Intergalactic is far more enticing to the public than probes. I, and I would bet most children, didn't dream of sending a probe to Mars, we dreamed of going ourselves.
That's why you choose the marshmallow now and can't wait "15 minutes". You want instant gratification now. I want the human race to move way out into the solar system, permanently, and in a big way.
And I don't believe the general public will fund it without the hope, however distant, of getting into space themselves. They have been promised too much that hasn't come true and scientists are currently telling them that they are doomed anyway.
> manned space travel is no longer the optimal way to explore or conduct research
With one exception, research into how people can travel in space.
In my mind, that research goal trumps every single other possible research target. Getting our species off this rock and spread out like so many seeds is the single most critical long-term goal for all humanity. No amount of soil surveys or robot comet missions will achieve this. No number of star maps, extra-solar planets, or infrared skycharts will actually get our species up and out.
Imagine all the science that Opportunity has performed. Now think what six astronauts with shovels and a mobile lab tent on Mars could do in the same time. Would it require more resources? Sure, I require more resources than my electronic keyboard here on Earth. But I'm more important.
You can do the same experiments inside the gravity well of Earth, without the extra cost of sending humans and all the survival equipment required.
With all the money that you save you can experiment with humans close to Earth and use the money you save to send many robots to do the actual exploration, which will survive longer than humans and do much more work.
Of course you won't get the same publicity. So maybe just for that it's better to send humans, but not for scientific reasons.
> You can do the same experiments inside the gravity well of Earth, without the extra cost of sending humans and all the survival equipment required.
No you can't. You simply can't put people on Mars without putting people on Mars. All that extra equipment is the experiment. Operating for years at a time in Mars local environment is the experiment. Getting humans out of Earth's gravity well and living, generationally on some other ball of rock (or in a habitat of some kind) is the experiment. You can't ever do those things without actually doing those things and doing that is the experiment.
The single most important question that we have to answer is this, can we or our descendants survive the cataclysmic destruction of our planet by colonizing space, or are we an evolutionary dead-end, destined to be snuffed out the first time the sun burps in our direction or an island sized boulder plows into Europe? Are we no better than all the other helpless animals who evolution didn't gift with the power of survival in the face of absolute destruction, or is that gift real? Are we just fancy, clothes wearing, monkeys?
Answering that question is answerable with only one experiment, and that's actually doing it. It's an endeavor that makes the necessity of something like the LHC look like child's play, but the answer it yields could be the difference between our collective termination and the future survival of our progeny.
No amount of simulations or probes can ever answer that. That's a path towards the slow extinction of our species, surrounded by the knowledge of the cosmos, as gathered by our instruments, but not our senses.
“If scientific knowledge was all we were after, then the Federation would have built a fleet of probes, not starships. Exploration is about seeing things with your own eyes.”
— Captain Kathryn Janeway, One Small Step, Star Trek Voyager Season 6, Episode 8
As ever I find myself inspired by Kerbal Space Program. I hate flying my kerbals anywhere, because irrationally I don't want them to die horrible flaming explosive deaths due to some error or miscalculation on my part. Instead I nearly always send probes - it's definitely cheaper, and it's totally guilt-free in the face of my almost-certain screw-ups.
That said, there's something deeply satisfying about flying my little green men somewhere, landing, and having a good walkabout. It isn't at all rational. I think real life is the same. There are plenty of places on Earth inimical to human life---Everest's death zone springs immediately to mind---and yet people travel to these places purely out of a sense of adventure. So too with space. "Because it's there" is a damn fine reason to go to the stars.
I was as excited to see Phillae land on a comet as I would have been if it were a human. It feels irresistible to me that robots are human's presence outside Earth. We're sharing the same network.
Still I'm not surprised if a permanent Moon base replaces ISS in the future. At that point, doesn't it make more sense to build on solid ground rather than in a low-orbit mecano bound to burn in the atmosphere?
Pretty sure as well that we are all underestimating leisure and entertainment as a driver of future space exploration. This is the true Jurassic Park. Air travel didn't become routine for science but thanks to tourists.
To be fair, air travel become routine because of a couple of wars.
I don't see people spending that much on leisure. People spend on food and energy, then tools they need for work. If any money (or credit) remains, then they spend on anything else.
Agreed. And this in turn implies that the best way to advance space exploration is not by doing space exploration, but by investing in AI development. When AIs become smart and autonomous enough, then money spent on actual space travel will again be well spent.
I've been trying to get this article some attention on HN, but it's fallen flat the three or so times I've submitted it. "The case for nuclear propulsion for spacecraft (2003)": http://www.spacedaily.com/news/nuclearspace-03h.html
The article's points are (a) there were some realistic strides towards long-term sustainable space exploration before the Apollo project, (b) the Apollo project was directly responsible for canceling funding towards these long-term projects, and (c) the Apollo project was nothing more than a machine to convert a huge quantity of cash into a one-time use spacecar to stick a pole in the moon.
It was particularly surprising to realize that there are, in fact, feasible ideas for real space exploration. Humanity just has to remember and decide to pursue it.
With respect, the comment that "the Apollo project was nothing more than a machine to convert a huge quantity of cash into a one-time use space-car to stick a pole in the moon" seems to drop an incredible amount of context.
I think the Apollo project (and Mercury, and Gemini, the programs which preceded Apollo) resulted in a massive amount of learning, technology development, progress in manufacturing know-how, etc.
How do you feel about the idea that microcontrollers would have been invented anyway, even if Silicon Valley hadn't established the industry? It's that kind of situation. The learning, technology development, and manufacturing know-how may still have came. We'll never know for certain, and I'm not trying to imply that the Apollo project did nothing for any of those things, but it was largely a political decision to cancel these long-term space exploration projects in favor of the US being able to thumb their nose at the Russians for a bit. (As opposed to those projects being canceled for scientific reasons like feasibility.)
Any form of adventure first need perform the "stick a pole somewhere" process (if returning home is expected). At the time, just getting there is an extraordinary act, requiring a supreme effort leveraging advanced technology and taking great risks. Several of the allegedly first discoveries of America (Lief Erikson, Christopher Columbus, others) were content to arrive, take a brief look 'round, and return home. Topping Mt. Everest involved little more than planting a flag and heading back down. Apollo, indeed, planted a pole - and even took time to drive around a little before heading back with a few rocks.
Early on, just getting there and coming back intact is hard enough. Get that process down first, then see what else can be done.
Methinks the real hindrance to further manned space exploration was: after great effort, we stood someone on a dead rock. Yeah, sorta interesting, but not really compelling; no really dramatic scenery, no minerals worth the cost of mining, too exhausting to think (after that huge effort) of the place of a jumping-off point for an orders-of-magnitude harder effort to go somewhere else not much more interesting when you actually get there. Fascinating, yes, but few people want to contribute vast sums, if not their very lives, to a long boring trip in a can (even with a Morale Officer) to a giant rock quarry. We're not talking the planet Pandora or some such here.
And per another poster's detailed list: it's very, very expensive to send a meatbag somewhere.
I don't believe we have a solution to human-vs.-machine question, which is better to go to space. On human side, many times both opponents and proponents of space robotics pointer out that for big exploration programs humans become more economical - as you still can't reproduce human abilities in space with robotics while spending the same resources, if you have big enough goals.
Humans have other advantages too. Majority of people in modern NASA workforce say that they become interested in space when watching human space programs. So far no robotic achievements have psychological impact equal to humans in space. Next, there is eternal "explorational" argument - you don't really "get" space into your domain until you're actually maintain physical presence in it. Unless you at least fly on LEO, you aren't in space. Until you fly to the Moon, you don't "use" it. Etc.
Next, while robotics is advancing with leaps and bounds, human spaceflight doesn't stand still. In 1990-s Dan Goldin, NASA administrator, ordered an evaluation of some options of going back to the Moon. The cheapest was using existing rockets - less than 30 tonns on LEO per launch - and the program was for less than a billion dollars. Note that a bunch of technologies used today in manned spaceflight are vastly superior to those used during Project Apollo.
Getting to orbit becomes cheaper and safer - SpaceX is another evidence to that, but it's not at the end of technical possibilities. When you get spaceflight cheap enough, there is no stop for curious individuals to go to the Moon in person. Same for Mars - at least.
What technologies will be employed for traveling in space - that's another matter. With cheaper and cheaper energy it will progressively make sense to make more and more safe - even if heavier - human spacecrafts. The more infrastructure in space we have - be it LEO stations, fuel depots on orbit, Moon-based fuel production, Mars navigational network etc - the easier it will be to launch both robots and humans. It's hard for me to see why we won't want to go.
Why, in good old Keynesian terms, did spending 4 % of the total budget on what could be described as a New Deal for engineering and scientists, was there supposedly so little ROI? That seems to be the argument from this article - we did not go back because it was too expensive. But if it brought more benefits than it cost, surely the expense is worth it?
I would have assumed economists would be all over NASA's accounts and the impact on the national debt?
It just seems a great natural experiment for spending as an economic influencer.
The telos of America is not ROI. The conquest of the continent was not really about monetary returns. You should think of space as a new manifest destiny.
Lots of interesting discussion here about space exploration, but I'd like to add a personal note. I grew up in Huntsville, Alabama, during the 60s, NASA's glory years. Huntsville is home to Marshall Space Flight Center, where my father, an electrical engineer, worked as a contractor, with Chrysler. He worked on parts of the Saturn V and, I think, Gemini. When the Apollo program shut down and NASA had to retrench, he was laid off at about age 50, along with many other scientists and engineers. Huntsville imploded. Some of the unemployed started high-tech companies, some found jobs elsewhere, many left aerospace entirely. Chrysler moved some operations there, but nothing was available for my father. Fortunately, he heard through a friend of a job at Goddard Space Flight Center, in Maryland. He got the job and we moved, taking a loss on the house we'd owned for twelve years. He spent the last 17 years of his career at Goddard. Aside from the bigger issues of Humanity's Destiny in Space, the end of Apollo had significant human costs and changed many lives, including mine. I work at Goddard now and have spent over twenty years of my career here. That probably wouldn't have happened had we not moved to Maryland in 1971, when Apollo ended.
Some media company (Google, Alibaba?) might fill up the sunny side of the Moon with a grid of photovoltaic cells 1 kilometer apart, then charge money to flash advertisements back at the Earth. They'd make a killing during solar eclipses, it would be like the Superbowl!
You would also need batteries that can charge for two weeks of lunar day, and then last for the two weeks of lunar night. And you would need at least 15 million of them at that scale.
If you could squash each unit down to just 1 kg and reduce your cost to only $1M per kg to the lunar surface, the whole project would only cost $15 trillion, which is only about a sixth of the entire global economy.
It would probably be cheaper to erect a giant space-screen that selectively redirects incident sunlight through optical fibers in a nearer Earth orbit. Rather than turn the Moon into a billboard, build an orbiting billboard that is the same apparent size as the Moon. Or bigger. Really spoil the view.
Batteries on the moon could be used incrementally, sending only 100 up at first in a 10 x 10 grid, and flashing back crude pictures or ideograms, even basic movies of McDonalds burgers, so there's free cash flow early on. An orbiting billboard, however, needs to be built all at once before it's useful, so it's a bigger upfront investment. Moon batteries can also be placed strategically to blend in with the topographical features already there, so instead of a Man in the Moon, we see a Man in the Moon drinking a can of Coke.
It was a great achievement to send humans to the moon, but I don't really see the point in going again. Or in sending humans to Mars. It won't be a place where people can live. No matter what happens to Earth, there will still be areas on it (or in it) that are more habitable to life than anywhere else in the solar system (and beyond). We could spend more time exploring the inside of Earth (and maybe creating small colonies there) than on the moon or mars.
We should go to Mars for the same reason we should climb Everest- because it is there. Neil Tyson has spoken very eloquently about this. Having something to strive for inspires people. It inspires children to become scientists, engineers, people who do something that nobody has ever done before, go somewhere that nobody has gone before. And that has untold, unimaginable benefits for all of humankind: https://www.youtube.com/watch?v=pUbOjZWjTLU
If both robotics and human spaceflight will become cheap enough, even the fact that, say, robotic flights are fixed times cheaper won't matter. You don't always refuse to get a cup of coffee just because it's several times more expensive than some alternatives. The absolute difference is small enough for you to just ignore the fixed relative difference.
The good news is that the ever-growing sophistication of mechanical devices gives our species incredible "virtual fingers" to probe and interact with the cosmos, whether for research, or industry (such as asteroid mining, and perhaps someday, long-term terraforming).
And of course, I hold out hope that our cyborg/android/AI great-grandchildren will someday roam the stars in a way that we primates can only dream of.